The present invention pertains to a hybrid stencil printing apparatus including a stencil-making/printing unit and other printing units based on printing methods other than stencil-making/printing unit uses, a control method thereof and a computer-readable recording medium for recording the same control program.
Conventionally, the stencil printing apparatus has been widely used for printing a large number of temporary printed sheets having a quick announcement property, such as advertisement papers folded into newspaper, real-estate advertisements, and communication papers from schoolteachers to parents, because it can print at high speed (120 pieces per minute) at a low running cost. The xe2x80x9ctemporary printxe2x80x9d mentioned here refers to, for example, prints, which are to be thrown away without being stored after its information communication purpose has been attained. Under such circumstances, it is important to suppress printing cost, and low-price paper such as pulp paper is often used as print paper.
Such a low-price paper has a feature that its surface is rough. Because emulsion ink used for the stencil printing apparatus has a high viscosity, the emulsion ink is not diffused through exudation when it is transferred to rough paper, enabling a favorable, highly precious picture to be printed.
Most stencil printing apparatus has a structure whereby a printing drum is detachably mounted. Therefore, by preparing printing drums filled with colored ink other than black ink and replacing the printing drum, various colors can be printed out. Further, by overlap-printing with plural printing drums, it is possible to obtain a print composed of plural printing colors so that only the portion desired to be stressed in an original is printed in red although the basic printing color is black. In this specification, printing with a single-color ink is called xe2x80x9cspot color printingxe2x80x9d in order to distinguish it from xe2x80x9cfull-color printingxe2x80x9d in which three process inks, which colors are cyan, magenta, yellow (CMY) are used.
However, if there is not sufficient room for storage, the number of available colors is restricted, because the printing drum requires a storage place. Although the stencil printing apparatus is capable of making full-color printing if printing drums filled with three process inks such as cyan, magenta, and yellow inks are employed, the registration accuracy of the current stencil printing apparatus is not sufficient, so that it is difficult to register the respective registrations of the cyan, magenta and yellow to such a fine extent without problems in practical use.
On the other hand, the ink jet printer is capable of achieving full color print at a registration accuracy high enough for practical use if provided with a monolithic ink cartridge in which cyan, magenta and yellow inks are integrated. However, because the ink of the ink jet printer has a low viscosity, if it is used on a cheap, rough-surfaced paper such as pulp paper for use in stencil printing machine, the ink is blurred in the directions of the paper fibers so that it blurs, and excellent quality print can not be provided. For this reason, in order to secure a high precision print in the ink jet printer, it is necessary to use special paper capable of suppressing blurring of the ink.
Although as described above, the stencil-printing machine can print a high precision image on rough surface paper, it requires considerable cost for spot color print and there is a problem with registration accuracy when full-color print is carried out.
On the other hand, although the ink jet printer can provide the spot color print and the full color print at such a registration accuracy without any problem in practical use, it cannot provide an excellent quality image on rough-surfaced paper.
Accordingly, the present invention has been achieved to solve the above described problem and therefore, an object of the invention is to provide a hybrid stencil printing apparatus, a method for controlling the hybrid stencil printing apparatus and a computer-readable recording medium for recording program for the same, capable of carrying out both spot color print and full color print at an excellent image quality even on a rough surface paper.
A hybrid stencil printing apparatus in one embodiment according to the present invention is characterized in that the hybrid stencil printing apparatus includes: a stencil-making/printing unit configured to perforate a stencil sheet corresponding to a desired image, to wind the stencil sheet around outer peripheral surface of a print drum, and to transfer a printing medium to the print drum with pressure, thereby printing the printing medium; an other-method image-formation unit configured to print the printing medium transferred on the same transfer passage as the stencil-making/printing unit according to a different printing method from the stencil-making/printing unit; and an image-formation unit selection-unit configured to input an original digital image, to determine attributes of each image portion of the inputted original digital image, and to allocate each image portion selectively to the stencil-making/printing unit and the other-method image-formation unit based on the determination result.
A method for controlling a hybrid stencil printing apparatus including a stencil-making/printing unit and an other-method image-formation unit, in one embodiment according to the present invention, is characterized in that the method includes: (a) inputting an original digital image, determining attributes of each image portion of the inputted original digital image, and allocating each image portion selectively to the stencil-making/printing unit and the other-method image-formation unit based on the determination result; (b) perforating a stencil sheet corresponding to the image allocated to the stencil-making/printing unit, winding the stencil sheet around outer peripheral surface of a print drum, and transferring a printing medium to the print drum with pressure and thereby printing the printing medium, in the stencil-making/printing unit; and (c) printing the image allocated to the other-method image-formation unit on the printing medium according to a different printing method from the stencil-making/printing unit in the other-method image-formation unit.
A computer-readable recording medium in one embodiment according to the present invention, recording a program for controlling a hybrid stencil printing apparatus including a stencil-making/printing unit and an other-method image-formation unit, is characterized in that the program includes: (a) inputting an original digital image, determining attributes of each image portion of the inputted original digital image, and allocating each image portion selectively to the stencil-making/printing unit and the other-method image-formation unit based on the determination result; (b) perforating a stencil sheet corresponding to the image allocated to the stencil-making/printing unit, winding the stencil sheet around outer peripheral surface of a print drum, and transferring a printing medium to the print drum with pressure and thereby printing the printing medium, in the stencil-making/printing unit; and (c) printing the image allocated to the other-method image-formation unit on the printing medium according to a different printing method from the stencil-making/printing unit in the other-method image-formation unit.
Other object, feature and effect of the present invention will be more apparent from the following detailed description with reference to the drawings below.